The present invention relates to equipment for feeding strip material, intended particularly for use in machines by which cigarettes and products of similar type are packaged.
Conventionally, cigarettes are packaged using automatic machines known as cigarette packers. Packets of cigarettes normally comprise a first inner wrapper of sheet material such as metal foil paper, enveloping a group of cigarettes, and a second outer wrapper of sheet material consisting in cardboard or paperboard, which encloses the inner wrapper and is openable at the top. In the case of rigid cigarette packets, the outer wrapper appears as a box and is furnished internally with a suitably contoured stiffening frame positioned to coincide with the openable top of the packet. Packets of cigarettes are also enveloped typically in an outer layer of flexible and transparent overwrapping material, such as cellophane.
By way of example, patent EP 0967161 illustrates a cigarette packet of the type in question, and a method of manufacturing such a packet. Cigarette packers function generally by feeding a continuous strip of sheet material such as metal foil paper from a roll to an operating station, where single portions of the strip are cut and folded around previously assembled groups of cigarettes to form the inner wrapper aforementioned. The products enveloped in the first inner wrapper are then directed into an operating station where the aforementioned second outer wrapper is added. The packets assembled in this way are then conveyed in line to a cellophaner, by which each one is covered in the aforementioned overwrapping of flexible transparent film.
It is also a common practice to add coupons to the packets, positioned between the first inner wrapper and the second outer wrapper and referred to generically as inserts. The coupons in question are cut from a roll of strip material and fed to a further operating station where each one is applied to the first inner wrapper containing the cigarettes.
Alternatively, packets of cigarettes may include leaflets, referred to as onserts, which are folded and printed with information about the particular product and/or with other sales information of whatever nature. In particular, these folded leaflets are positioned usually between the packet and an overwrapping film of transparent flexible material, in such a way as to remain visible throughout the distribution and shelf life of the unopened packet. More exactly, the folded leaflets are applied generally to packets of cigarettes, typically to the rear face of the packet, before the selfsame packets are overwrapped in the transparent film material.
Patent application IT BO2009A000425 discloses a method and equipment for preparing and applying folded leaflets wherein the single leaflets, cut from a strip material, are folded around respective winding members. Each such winding member is designed to take up and retain a portion of the single leaflet, then caused to rotate in close proximity to a fixed restraint by which the leaflet is engaged and forced to wrap around the winding member.
With cigarette packers currently in use, however, it is not possible to effect a swift and simple changeover from one production method to another, alternately applying coupons (inserts) or leaflets (onserts) to packets as and when required.
The object of the present invention is to overcome the aforementioned drawback by providing equipment that will be capable of feeding strip material used in the application either of coupons, as inserts, or of leaflets, as onserts, to products such as packets of cigarettes and the like, in machines by which products of the type in question are normally packaged.
A further object of the present invention is to provide equipment for use in conjunction with packaging machines capable of high operating speeds.
Yet another object of the invention is to provide equipment characterized by simple design, in terms of construction and operation, such as will be dependable, versatile, and relatively inexpensive to carry into effect.